Behavioural and weight status outcomes from an exploratory trial of

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Behavioural and weight status outcomes from an exploratory trial of the Healthy Lifestyles Programme (HeLP): a novel school-based obesity prevention programme Jennifer J Lloyd,1 Katrina M Wyatt,1 Siobhan Creanor2

To cite: Lloyd JJ, Wyatt KM, Creanor S. Behavioural and weight status outcomes from an exploratory trial of the Healthy Lifestyles Programme (HeLP): a novel school-based obesity prevention programme. BMJ Open 2012;2:e000390. doi:10.1136/ bmjopen-2011-000390 < Prepublication history for

this paper is available online. To view this file please visit the journal online (http://dx. doi.org/10.1136/ bmjopen-2011-000390). Received 14 September 2011 Accepted 6 March 2012 This final article is available for use under the terms of the Creative Commons Attribution Non-Commercial 2.0 Licence; see http://bmjopen.bmj.com

1

Institute for Health Service Research, Peninsula College of Medicine and Dentistry, University of Exeter, Exeter, UK 2 Centre for Health and Environmental Statistics, University of Plymouth, Plymouth, UK Correspondence to Dr Jennifer J Lloyd; [email protected]

ABSTRACT Objectives: To assess the behavioural and weight status outcomes in English children in a feasibility study of a novel primary school-based obesity prevention programme. Design: Exploratory cluster randomised controlled trial of the Healthy Lifestyles Programme. Setting: Four city primary schools (two control and two intervention) in the South West of England. Participants: 202 children aged 9e10 years, of whom 193 and 188 were followed up at 18 and 24 months, respectively. No child was excluded from the study; however, to be eligible, schools were required to have at least one single Year 5 class. Intervention: Four-phase multicomponent programme using a range of school-based activities including lessons, assemblies, parents’ evenings, interactive drama workshops and goal setting to engage and support schools, children and their families in healthy lifestyle behaviours. It runs over the spring and summer term of Year 5 and the autumn term of Year 6. Primary and secondary outcomes: Weight status outcomes were body mass index, waist circumference and body fat standard deviation scores (SDS) at 18 and 24 months, and behavioural outcomes were physical activity, television (TV) viewing/screen time and food intake at 18 months. Results: At 18 months of follow-up, intervention children consumed less energy-dense snacks and more healthy snacks; had less ‘negative food markers’, more ‘positive food markers’, lower mean TV/screen time and spent more time doing moderate-vigorous physical activity each day than those in the control schools. Intervention children had lower anthropometric measures at 18 and 24 months than control children, with larger differences at 24 months than at 18 months for nearly all measures. Conclusions: Results from this exploratory trial show consistent positive changes in favour of the intervention across all targeted behaviours, which, in turn, appear to affect weight status and body shape. A definitive trial is now justified.

Lloyd JJ, Wyatt KM, Creanor S. BMJ Open 2012;2:e000390. doi:10.1136/bmjopen-2011-000390

ARTICLE SUMMARY Article focus -

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To present behavioural and weight status outcomes from an exploratory cluster randomised controlled trial of a novel school-based obesity prevention programme with English primary school children. To present sample size estimates required for a definitive trial of the programme based on outcome results, attrition rates and estimates of the intraclass correlations of the outcome measures.

Key messages -

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The Healthy Lifestyles Programme (HeLP) has been developed using behaviour change theory and extensive stakeholder involvement to engage and support children and their families in healthy lifestyles. Behavioural and weight status outcomes at 18 and 24 months from this exploratory trial (Phase 3 pilot) show consistency in the direction of effects, all in favour of the intervention, demonstrating ‘proof of concept’. Results from the exploratory trial have provided sufficient evidence to support the evaluation of HeLP in a full-scale trial.

INTRODUCTION During the past 3 decades, the prevalence of obesity in children in Europe has risen dramatically.1 In the UK, the Health Survey for England reported that 19% of girls and 18% of boys aged 11e15 years were obese and 34% of girls and 33% of boys were overweight or obese.2 The National Child Measurement Programme in England reported that by age 10e11 years, one in three children were either overweight or obese.3 Being overweight in childhood is 1

Results from an exploratory trial of the Healthy Lifestyles Programme (HeLP) ARTICLE SUMMARY Strengths and limitations of this study -

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The HeLP intervention has undergone a systematic development process using research evidence, behavioural theory, stakeholder consultation and piloting. This has enabled the researchers to gain a deeper understanding of the context in which the intervention was to be delivered in order to maximise engagement at all levels. The exploratory trial presented in this paper (Phase 3 pilot) has demonstrated not only that the design of the trial is feasible, with outcome data obtained from 92% of the original cohort at 24 months after transition to secondary school, but also that behavioural and weight status outcome measures at 18 and 24 months show consistency in the direction of effects (although the differences are relatively small), all in favour of the intervention, demonstrating ‘proof of concept’. This shows that a definitive trial of HeLP is both feasible and justified. The study was conducted in the South West of England, where the population is predominantly white, and although there are areas of deprivation, none of the four schools had $25% of children eligible for free school meals (the national average of proportion of children eligible for free school meals). However, the intervention has been developed to allow the flexibility and adaptation to ensure that it is recognising and responding to the local needs of children and families from different socioeconomic and ethnic groups while still maintaining fidelity. Food intake and television (TV) viewing/screen time were self-reported, and although children were asked to sit in their literacy tables so that appropriate support could be provided to each child during completion, the information children are able to provide is limited. We did, however, go to great lengths to ensure that the questionnaires were simple and presented in such a way so as to trigger recall.

associated with adverse consequences, including metabolic abnormalities, increased risk of type II diabetes and musculoskeletal and psychological problems.4 A recent systematic review showed that the risk of overweight children becoming overweight adults was at least twice as high as for normal weight children,5 and more contemporary data, from a large prospective cohort of children born in the South West of England in 1991/ 1992 (Avon Longitudinal Study of Parents and Children), showed that the 4-year incidence of obesity was higher between the ages of 7 and 11 years than between 11 and 15 years, suggesting that mid- to late childhood (around 7e11 years) may merit greater attention in future obesity prevention interventions.6 Obesity results from an imbalance between consumption and expenditure of energy. Epidemiological studies suggest a number of risk factors, the strongest of which is having one or more overweight parents.7 There are also strong associations between the risk of overweight and socioeconomic status, diet, physical activity levels and other lifestyle factors.8 At a population level, the consumption of processed and fast food, including sweetened fizzy drinks, has increased while that of fruit and vegetables has declined and portion size in prepackaged food has increased substantially.9 In addi2

tion, the National Travel Survey10 has shown that, since the 1970s, children’s transport activity (eg, walking or cycling to school) has been in decline. Evidence about the relationship between physical activity, sedentary behaviours and childhood obesity is scarce with reviews of physical activity and obesity prevention reporting inconsistent results.11 12 Using data from the Avon Longitudinal Study of Parents and Children, Riddoch and colleagues13 found strong associations between children’s fat mass at age 14 and their physical activity at age 12. Compared with previous generations, children in the UK spend more time participating in sedentary activities, with research suggesting that children spend an average of 4.5 h a day looking at a screen.14 Some studies have reported an association between time spent watching TV and obesity.15 Not only is TV viewing a sedentary activity, but it is also positively correlated with total calorific intake16 and the consumption of snack foods.17 Schools have the potential to play a critical role in the prevention of overweight and obesity, and the more recent development of community-wide multisite approaches often use school-based interventions as part of the overall programme of events.18 19 Schools’ existing organisational, social and communication structures provide opportunities for regular health education and for the creation of a health-enhancing environment and, if school-based interventions are developed in a systematic way involving stakeholders and appropriate piloting phases, they have the potential to reach children and their families across the social spectrum. The most recent systematic review (2008) of controlled trials of school-based interventions concluded that interventions that aim to increase activity and reduce sedentary behaviour and affect diet may be more effective in preventing children becoming overweight in the long term.20 The Healthy Lifestyles Programme (HeLP) is an innovative school-based intervention that aims to deliver a general healthy lifestyle message encouraging a healthy energy balance. The programme takes a population approach, seeking to change behaviour at a family as well as at an individual and school level. The development of HeLP followed the MRC guidance for the development and evaluation of complex interventions21 involving careful theoretical derivation of behaviour change techniques (BCTs)22 and three phases of iterative pilot work.23 Phase 3 was the exploratory randomised controlled trial (RCT) to assess, for schools, children and their families: recruitment and retention in control and intervention schools; feasibility and acceptability of the intervention and of future trial outcomes measures and facilitators and barriers to uptake of the intervention. In addition, data from this trial would help us in calculating the sample size required for a full-scale trial. Here we present the behavioural and weight status outcomes from the exploratory RCT and the estimation of the sample size required for a definitive evaluation of the programme.


Results from an exploratory trial of the Healthy Lifestyles Programme (HeLP) METHODS Study design This is an exploratory cluster RCT of the HeLP intervention, in Exeter (a city in the South West of England), involving 202 children aged 9e10 years. There is little ethnic mix in the South West, with the majority of the population being ‘white’. Although overall socioeconomic status for the area is higher than average; within Exeter, there are some areas with quite severe deprivation. All state primary and junior schools in Exeter were eligible to take part if they had at least one single age Year 5 class (9e10-year-olds) (ie, not mixed classes, 8e10- or 9e11year-olds). Schools were recruited via the local network of primary school head teachers. Of the 11 eligible schools in Exeter, eight expressed an interest from which four schools (with a total of seven Year 5 classes) were randomly selected to participate and randomly allocated to intervention or control using a telephone-based randomisation service involving a statistician independent of the research. All parents of children were sent an information pack with an opportunity to opt-out of the study. If the optout form was not returned within 2 weeks, consent was inferred. The class teacher gave daily oral reminders to the children over this 2-week period to ensure that they and their parents had read the information sheet. Baseline measures were taken prior to schools being randomised to control or intervention groups. Intervention HeLP is a multicomponent four-phase programme delivered to 9e10-year-olds over three school terms (spring and summer term of Year 5 and autumn term of Year 6). The programme is based on the Information, Motivation and Behavioural Skills Model,24 which proposes that adequate information, motivation and behavioural skills are essential to behaviour change. Information, Motivation and Behavioural Skills Model has been demonstrated to provide an effective basis for behaviour change interventions in other domains25 26 and aims to deliver a general healthy lifestyle message encouraging a healthy energy balance. Within this context, three key behaviours are emphasised: a decrease in the consumption of sweetened fizzy drinks, an increase in the proportion of healthy snacks (HS) to unhealthy snacks consumed and a reduction in television (TV) viewing and other screen-based activities. These messages are consistent with the strategies suggested in the UK National Institute for Clinical Excellence (NICE) guidance on the prevention of overweight and obesity in adults and children.27 We hypothesise that targeting information, motivation and behavioural skills will lead to the adoption of mediating behaviours, which will, in turn, lead to improvements in diet and physical activity thus preventing excessive weight gain. These mediating variables and behaviours will interact to strengthen the engagement of children and their parents throughout the course of the intervention. Figure 1 provides a representation of this process indicating the feedback loops.

An Intervention Mapping approach,28 involving considerable stakeholder consultation and pilot work, was undertaken to link theory to specific BCTs29 30 and methods of delivery22 that were suitably engaging and compatible with the existing school curriculum. Table 1 shows each phase of HeLP, the targets of change, the BCTs used and the method and agent of delivery. Key to engaging and motivating the children are the highly inclusive and interactive drama activities, which are built around four characters (Disorganised Duncan, Football Freddie, Snacky Sam and Active Amy) with whom the children identify. During the Healthy Lifestyles Week (Phase 2), children work closely with the character most like them to help them to change their behaviours. In Phase 3, the children reflect on their own lifestyle behaviours around diet and activity and set simple goals with their parents. The programme has been specifically designed so that the function of each phase is clearly defined and delivered appropriately, while the precise content can be adapted to relate to children from differing ethnic and social backgrounds. During the drama workshops, children co-create scenes with the actors and provide their own ideas and solutions to problems faced by the characters. Outcome measures Baseline height, weight, waist circumference, % body fat, food intake, TV viewing/screen-based activity and physical activity were collected at the start of the school year, in the autumn term (October/November 2008) prior to randomisation of schools. These same measures were then collected 18 months post-baseline (June/July 2009), and anthropometric measures only were collected 24 months post-baseline (October/November 2010), after the children had moved to secondary school. Anthropometric All anthropometric measures were taken by an independent assessor who was blinded to each child’s allocated group. For the anthropometric measures, children were asked to remove their shoes and socks. Height was measured using a portable SECA stadiometer (Hamburg, Germany) and recorded to an accuracy of 1 mm. Weight and body fatness was measured using the Tanita SC330 portable body composition analyser (UK Ltd, Middlesex, UK). Weight was recorded to within 0.1 kg. Body fatness was estimated from leg-to-leg bioelectrical impedance. Waist circumference was measured using a non-elastic flexible tape 4 cm above the umbilicus. Behavioural Food intake was assessed using an adapted version of the validated Food Intake Questionnaire,31 a recall method that asks whether specific foods were consumed the previous day. Children completed the Food Intake Questionnaire twice, during school hours, in order to obtain a weekday and weekend food intake. These results were then combined and weighted to calculate the mean number of different HS, energy-dense snacks (EDS),


3

Results from an exploratory trial of the Healthy Lifestyles Programme (HeLP)

Figure 1

The Healthy Lifestyles Programme (HeLP) process model. BMI, body mass index.

positive (PM) and negative (NM) foods markers consumed each day. TV viewing/screen-based usage was assessed using an adapted version of the validated Children’s TV Viewing Habits Questionnaire.32 Participants were asked to record the time (in minutes) they usually spent watching TV or doing other leisure time screenbased activities on weekdays before school, before tea and after tea and on the weekend (Saturday and Sunday morning, afternoon and evening). The results were then combined and weighted to calculate the mean time spent watching TV/doing leisure time screen-based activities each day. Additional information on the number and location of TV sets and rules in the home regarding TV viewing and screen-based usage was also collected. Questionnaires were completed during class time, where children were asked to sit in their literacy groups (table groupings based on their ability in literacy). JJL instructed the class on how to complete the questionnaires and, with the class teacher, learning support assistant, and an additional researcher assisted individual 4

children where necessary. Physical activity was measured in one randomly selected class per school using a GT1M Actigraph (Actigraph LLC, Pensacola, Florida, USA: http://www.theactigraph.com), attached to a flexible elastic belt fastened securely round the waist, which children were asked to wear during waking hours over seven consecutive days (five weekdays and two weekend days). As the device is not waterproof, children were instructed to remove it for water-based activities and record on their log sheet the reason for removal and the duration of this non-wear time. Data management Anthropometric and questionnaire data were entered into a specifically designed database. Ten per cent of entries (using a random number generator) were subsequently checked by a second researcher revealing only two data entry errors. The raw accelerometry data from the pre- and post-time points were processed using kinesoft software (V.3.3.55)



Summer term (Year 5)

Personal goal setting with parental supportdgoals set during week following drama

Phase 3

Summer term (Year 5)

Intensive healthy lifestyles weekd1 week

Phase 2

Spring term (Year 5)

Increase awareness of own behaviour Increase self-efficacy for Change Develop Planning skills Increase parental support

Increase self-efficacy for behaviour change Strengthen relationships with schools, children and families Increase knowledge Increase self-awareness Increase self-efficacy Develop communication and problem-solving skills Increase social support (school, peer and family)

Establish relationships with schools, children and families Raise awareness and increase knowledge Promote positive attitudes and norms towards healthy eating and physical activity

Phase 1

Creating a supportive context

Change targets

Intervention phase

Prompt identification as a role model

Goal setting (behaviour) Problem solving/barrier identification Plan social support Provide information on where and when to perform a behaviour Agree behavioural contract

Provide information on healthebehaviour link Problem solving/barrier identification modelling/ demonstrating behaviour Prompt identification as a role model Communication skills training Teach to use prompts and cues Self-monitoring

Whole-school assembly (1) (20 mins) Newsletter articles (3) (over the spring term) Activity workshops (2) (parents observe) (1.5 h)

Provide information on behaviourehealth link Provide information on healthebehaviour link Modelling/demonstrating behaviour Prompt identification as a role model Provide information on behaviourehealth link Skill building

HeLP coordinator

1:1 goal setting interview (1) (goals sent home to parents) (10 mins) Parent’s evening (1) (child involvementdForum Theatre) (1 h)

HeLP coordinator/ drama group Continued

HeLP coordinator/ class teacher HeLP coordinator/ parents

Drama group

xDrama (5) (afternoon) (forum theatre; role play; food tasting, discussions, games, etc) (2 h)

Self-reflection questionnaire (1) (40 mins) Goal setting sheet to go home to parents to complete with child (1) (10 mins)

Class teacher

Class teachers/ HeLP coordinator/ drama group

Professional sportsmen/dancers

HeLP coordinators

HeLP coordinators

Agent of delivery

*PSHE lessons (5) (morning) (1 h)

Parents’ evening (1) involving child performances; (1 h)

Method (frequency and duration)

BCTs

Table 1 Intervention phases, change targets, BCTs and the method and agent of delivery

Results from an exploratory trial of the Healthy Lifestyles Programme (HeLP)

5

6

Prompt review of behavioural goals Prompt barrier identification and resolution Coping plans

*PSHE e Personal, Social and Health Education xThe drama framework includes 4 characters, each represented by one of the actors, whose attributes related to the three key behaviours. Children choose which of the characters they most resemble then work with that actor to help the character learn to change their behaviour.

Children to all other year groups in the school HeLP coordinator Prompt practice Autumn term (Year 6)

Increase parental support

Drama group Class teacher

Whole-school assembly (1) (20 mins) Drama workshop (1) (1 h) *PSHE lesson (1) (1 h) Class to deliver assembly about the project to rest of school (1) (20 mins) (parents invited to attend) 1-to-1 goal supporting interview to discuss facilitators/barriers and to plan new coping strategies (1) (10 mins) (renewed goals sent home to parents) Prompt self-monitoring Prompt intention formation Follow-up prompts Reinforcement activities

Develop monitoring and coping skills

HeLP coordinator Drama group Newsletter articles (2) (over the autumn term) Provide information on healthebehaviour link Increase self-awareness and prioritise healthy goals. Consolidate social support Phase 4

Agent of delivery Method (frequency and duration) BCTs Change targets Intervention phase

Table 1 Continued

Results from an exploratory trial of the Healthy Lifestyles Programme (HeLP) and quality control checks carried out. To be included in the analysis, participants had to have at least 10 h of wear time a day on three weekdays and one weekend day. Days were counted if participants accrued 10 h of wear time during the day. Periods of non-wear time were classified as 30 min of zero counts. Those who failed to meet the inclusion criteria were excluded from subsequent analysis. Usable accelerometry data were obtained for 104/111 (95%) and 95/111 (85%) participants at baseline and 18 months of follow-up, respectively. Eligible days of data were organised into time spent in each activity intensity per day. Activity intensity categories were classified using the following previously published cut points (sedentary: 0e299; light: 300e3580; moderate: 3581e6129; vigorous: $6130).33 Statistical analysis As this was an exploratory study, we sought to use the results, including the attrition rates and estimates of the intraclass correlations of the outcome measures, to help us plan a definitive cluster RCT, including estimating the sample size needed for such a definitive trial. The main analysis of the effect of the exploratory trial was undertaken on an intention-to-treat basis. As there was only a small number of missing data for some of the outcomes (see figure 2), the analysis was based on all the available data, with no imputation for missing data. As this was an exploratory trial involving only four schools, only cluster-level analyses were undertaken34 35; this meant that the analyses could not be adjusted for individual-level covariates (eg, baseline measures). As there were varying numbers of children in each school, the analyses were weighted by cluster size35 36; inverse variance weighting was not used, given the uncertainties in estimating the intraclass correlation coefficients (ICCs). Differences between the intervention and control groups are presented, together with 95% CIs. Unadjusted results (ie, without clustering being taken into account) are also presented, in order to allow comparison of the precision of the estimates of the effect of the intervention. ICCs (and 95% CIs) were calculated for selected outcomes. All analyses were undertaken in STATA V.11.1. RESULTS Recruitment and participant characteristics at baseline Figure 2 shows the flow of participants through the trial37 and follow-up of anthropometric measures at 18 and 24 months. The intervention group consisted of two primary schools, one with 170 children on the school roll (13% eligible for free school meals (FSM) and one larger primary school with 384 children on the roll (2.6% FSM). The control group consisted of two primary schools, one with 317 on roll (14% FSM) and the other with 364 on roll (6% FSM). Table 2 shows that the intervention and control groups were generally comparable at baseline with the percentages of children overweight/obese being 24% and 26%, respectively.38 While there was higher percentage of obese and a higher percentage body fat


Results from an exploratory trial of the Healthy Lifestyles Programme (HeLP) TV viewing/screen time was 2.6 h a day, which mirrors national data for 4e15-year-olds.16 The percentage of children who had TVs in their bedrooms was higher in the control group compared with the intervention group; however, the percentage of children who had no rules regarding screen time was higher in the intervention group compared with the control group. Both groups spent a similar amount of time per day in sedentary activities but differed slightly in time spent in moderate-vigorous physical activity; however, this varied greatly between children (range: 13.7e104 min). Mean sedentary time (including sleep time) for all children was 16.2 h/day. Intervention and control group comparisons at follow-up Anthropometric Anthropometric follow-up data were collected for 193 and 187 participants at 18 and 24 months, respectively (94% and 92% of the original cohort of 202 children). Table 3 shows the comparisons of the main outcomes at 18- and 24-month follow-ups between the children in the intervention schools and control schools. Children in the intervention schools typically fared better than those in the control schools having, on average, lower anthropometric measures at 18 and 24 months with larger differences at 24 months than at 18 months for all measures except percentage body fat standard deviations (SDs). At 18 months, the proportion of overweight and obese children had increased by 6% in the control schools (from 26% (31/122) to 32% (38/119)), while remaining at baseline levels in the intervention schools (24% (18/74)). At 24 months, the proportion of overweight/obese children remained at 32% (36/114) in the control schools and decreased slightly to 22% (16/73) in the intervention schools. The waist circumference data show similar proportions at baseline ($85th centile) shifting to an 8.7% difference in favour of the intervention at 24 months.

Figure 2 Flow chart of participants through the trial and numbers of children from whom measures were collected. Anthrop, anthropometric; FIQ, Food Intake Questionnaire; PA, physical activity.

($85th and